Myeloid tissue, in the bone marrow sense of the word 'myeloid' ('myelo-' + '-oid'), is tissue of bone marrow, of bone marrow cell lineage, or resembling bone marrow, and myelogenous tissue ('myelo-' + '-genous') is any tissue of, or arising from, bone marrow; in these senses the terms are usually used synonymously, as for example with chronic myeloid/myelogenous leukemia.

It is a tissue within red bone marrow that produces the blood cells. It is found around the blood vessels and contains various cells that are precursors of the blood cells.

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